The square was transformed into a sea of orange, as demonstrators waved coloured balloons, flags and banners.

Giant posters proclaimed "Gush Katif, I swear fidelity" and "Samaria, I swear fidelity" - references to a doomed settlement bloc and the biblical Hebrew name for the northern West Bank.

"Nothing is over. We must go to the south, on the roads. God will hear us," Yigal Kamineski, rabbi of Gush Katif, told the crowd.

Leaflets were distributed, telling supporters of the settler movement where to go as the pullout begins, to try to block the roads into Gaza and disrupt the process.

The square where the rally was held is the place where former Israeli Prime Minister Yitzhak Rabin was shot dead in 1995 by a right-wing Jewish gunman opposed to the peace accords with the Palestinians.

The demonstration comes a day after tens of thousands of Orthodox Jews held a mass prayer gathering at the Western Wall in Jerusalem - Judaism's holiest site - against the impending pull-out.

The withdrawal of settlers from the Gaza Strip is due to get under way on Wednesday next week, with a further withdrawal from four settlements in the West Bank soon afterwards.